22. DelayBox: Per-Flow Delay and Loss

DelayBox is an ns node that should be placed in between the source and
destination nodes. With Delaybox, packets from a TCP flow can be
delayed, dropped, and/or forced through a bottleneck link before being
passed on to the next node. A distribution can be used to specify
delay, loss, and/or bottleneck link speed for a source - destination
pair. Each flow between that source - destination pair draws from the
distribution to determine its characteristics. Delays in DelayBox are
per-flow, rather than per-packet. Since DelayBox distinguishes between
flows, the fid_ variable (flow identifier) should be set for
each flow in the simulation. DelayBox can be used with both Tcp and
FullTcp agents.